Make it possible to remap 'a' to another character.

[xbot]

The character 'a' is conflicted with the argument object of targets.vim, to me, the argument object is used more frequently than the after object, so I want to keep 'a' for the argument object and map another character (e.g. A) to after object.

Sadly, for now, I can only remap the argument object, because targets.vim provides a solution for this:

        autocmd User targets#mappings#user call targets#mappings#extend({ 
            \ 'A': {'argument': [{'o': '[([]', 'c': '[])]', 's': ','}]}, 
            \ }) 

But what I want is the opposite.